The reason we don't live in sub third world conditions like our ancestors of the 1700s is that with the Industrial Revolution, a few % of jobs have been automated each year.
Through this history people have always been worried about those whose jobs are automated, but they've always, on average at least, managed to find new and better paying jobs.
It's important to understand that 3.5m jobs won't disappear in a month. It will take at least a decade to switch around an industry this big, and people will have time to adjust.
Also, this means transportation will be cheaper and faster (computers don't need sleep), which benefits everyone.
> No society where an average person - of average intelligence, average skills, average potential - cannot make a good living for themselves, can survive as a civilized society.
I'm actually also worried about this, but I think it's a separate issue.